package org.example.Greedy_Algorithm;

public class agiotage {
    public static void main(String[] args) {
        //买卖股票的最佳时机 II

        //给你一个整数数组 prices ，其中 prices[i] 表示某支股票第 i 天的价格。
        //在每一天，你可以决定是否购买和/或出售股票。你在任何时候 最多 只能持有 一股 股票。你也可以先购买，然后在 同一天 出售。
        //返回 你能获得的 最大 利润 。
        int[] prices = {2, 1, 2, 1, 0, 1, 2};
        int i = maxProfit(prices);
        System.out.println(i);
    }

    //借鉴修改,不需要考虑那天的利润最大，只要比昨天贵就卖，二者策略的效果一样
    public static int maxProfit(int[] prices) {
        int money = 0;
        for (int i = 0; i < prices.length - 1; i++) {
            if (prices[i] < prices[i + 1]) {
                money = money + (prices[i + 1] - prices[i]);
            }
        }
        return money;
    }

    //1ms还行吧
    public static int maxProfit2(int[] prices) {
        int money = 0;
        int buy = -1;
        int sell = -1;
        for (int i = 0; i < prices.length - 1; i++) {
            if (prices[i] < prices[i + 1] && buy == -1) {
                buy = prices[i];
                sell = prices[i + 1];
            } else if (prices[i] < prices[i + 1] && buy != -1) {
                sell = prices[i + 1];
            } else if (prices[i] > prices[i + 1] && buy != -1) {
                money = money + (prices[i] - buy);
                buy = -1;
                sell = -1;
            }
        }
        return money + sell - buy;
    }
}
